1. Field of the Invention
The present invention relates to an enhanced 8 vestigial sideband (E8-VSB) receiver, which can receive a plurality of sets of enhanced data, each set of data being encoded by a different code rate, and more particularly, to a VSB receiver having an enhanced Viterbi decoder.
2. Discussion of the Related Art
Since the second half of 1998, the United States of America has adopted an advanced television systems committee (ATSC) 8 vestigial sideband (VSB) transmission method as the 1995 standard for broadcasting. Presently, the Republic of Korea is also providing broadcast programs by adopting the ATSC 8VSB transmission method as the standard for broadcasting. Such ATSC 8VSB transmission method has been established for the essential purpose of high definition imaging.
However, a system that may deteriorate the picture quality, yet stably receive incoming images, or a transmission standard for a system enabling data to be received with more stability as compared to video signals, due to the contents of the data, has also been on demand in the ATSC 8VSB transmission method. In addition, such additional transmission standards are to be regulated within the scope of not affecting the system for receiving the conventional ATSC 8VSB signal. And, also, the receiver of a newly established standard is regulated to be able to receive both the conventional ATSC 8VSB signal and the enhanced 8-VSB (hereinafter referred to as E8-VSB) signal. Accordingly, the E8-VSB system adopts the conventional 8VSB system and adds new types of services, which enable more enhanced reception of signals to be performed. Furthermore, due to the newly added services, the conventional services are also enabled to perform stable receiving functions.